For the stringer stairs project at the Berlin Institute for Medical Systems Biology (BIMSB), being part of the MDC, the Berlin Staab architects consulted the renowned MetallArt Treppen GmbH. Considering the comprehensive expertise and the employed state-of-the-art technologies the Berlin Max Delbrück Center, as the owner, accepted the internationally recognised staircase builder based in Baden-Wuerttemberg.
A show piece for innovative craftsmanship
All five floors in the new built Max Delbrück Center for Molecular Medicine in Berlin (MDC) are connected by the stringer stairs with their parapet-high steel balustrades. It was highly challenging to perform the 3D measurement for this project as the oval openings at each of the concrete ceilings are positioned offset to one another in order to obstruct the view to the highest storey. Instead, there is an open sight on the sophisticated solutions of the stringer stairs and the technical refinements. All flights of the stairs between the single floors are vertically designed and their self-supporting structure results in the inspiring sculptural appearance of the stringer stairs.
Staircase architecture featuring an harmonious look
The stringer stairs are complemented by the horizontal balustrade stringers at the elliptical slab edges. Beside their exceptional shape there are however further convincing aspects characterising these stringer stairs. One of them are the tangentially designed connections of the single components at the rounded and curved sections which increase the smooth and harmonious appearance of the stringer stairs.
• 115 risers without intermediate landings
• construction according to DIN 18065
• flight width 1.380 mm
• floor-to-floor height approx. 4.000 mm
A high level of accuracy was required for the tread step construction as the overhang between the treads and risers only amounted to 2 mm. Another challenge was the evenly execution of the chamfer accross the whole tread width. The ascending handrail is installed corresponding to the geometry of the stringer stairs. It consists of a bent round tube and is connected to the outer stringer.
Assembly of the stringer stairs
Due to its considerable dimensions the overall construction could not be lifted or transported into the buidling in one piece. Thus, the technicians divided the stringer stairs into four transportable elements per floor. On site the stringer stairs and the balustrades were installed bottom-up by the experts from Salach. They used a mini-crane which could be extended up to the 3rd floor. Subsequently the construction elements from the 3rd to the 5th storey were fitted by means of a rollable lift construction. This technical device was specially developed by the MetallArt staircase experts. To obtain a regular and homogenous look all joints and seams were properly grinded, polished and reworked with a primer.
As additional services MetallArt calculated and produced a verifiable structural anlysis as well as the vibration resistance verification for the stringer stairs.